Private patients are twice as likely to have pre-planned Caesarean sections as women whose treatment is publicly funded, according to new figures that lend support to the theory that some mothers are "too posh to push".

One in five (21%) private patients have a scheduled C-section, compared with just 8.9% of publicly funded ones, the study found.

Researchers examined 30,000 women who gave birth at a hospital in Ireland that caters for both private and public-funded patients between 2008 and 2011. Around one in five of the women paid for their treatment themselves.

The research, published in the journal BMJ Open, found that overall 34.4% of privately paying mothers had a C-section compared to 22.5% of public patients.

The "greatest disparity" noted between the mothers was the rates of scheduled C-sections, they found.

For first time mothers, 11.9% of private patients had pre-planned surgery compared with 4.6% of those whose care was paid for by the public purse.

"We found that private patients are more likely than public patients to have an operative vaginal delivery or a Caesarean section. The greatest disparity is for scheduled Caesarean sections, and twofold differences persist even after adjustment for sociodemographic, medical and obstetric factors.

"The differences observed in relation to operative deliveries were not explained by higher rates of medical or obstetrical complications among private patients."

Janine Stockdale, research fellow at the Royal College of Midwives said it may throw a spotlight on the high rates of Caesarean sections in western Europe.